Results 21 to 30 of about 84,846 (229)
Tähistaeval põhinevatest uskumustest III Vana-Hiina [PDF]
Mäetagused, 2002 The article concerns Chinese astral myths, calendar and astrology. Chinese creation myths concern also the creation of the Sun, Moon and stars. The heavenly bodies are constantly endangered by the sky dragon that now and then catches them, probably a ...
Enn Kasak
doaj
Shocklets in the Comet Halley Plasma [PDF]
, 2020 Dust acoustic (DA) waves evolving into shocklets are investigated in the Comet Halley plasma system relaxing to Maxwellian, Kappa and Cairns distributions. Here dynamics of dust is described by the fully nonlinear continuity and momentum equations. A set of two characteristic wave nonlinear equations is obtained and numerically solved to examine the DA
arxiv +1 more source
A model for the common origin of Jupiter family and Halley type comets [PDF]
Earth, Moon, and Planets, 2013, Volume 110, Issue 1-2, pp. 105-130, 2014 A numerical simulation of the Oort cloud is used to explain the observed orbital distributions and numbers of Jupiter-family and Halley-type short-period comets. Comets are given initial orbits with perihelion distances between 5 and 36 AU, and evolve under planetary, stellar and Galactic perturbations for 4.5 Gyr.
arxiv +1 more source
THE EFFECT OF A TRANS-PLUTONIAN PLANET ON HALLEY'S COMET
, 1972 An orbit and mass for a hypothetical trans-Plutonian planet is determined which reduces the residuals in the time of perihelion passage of Halley's comet at the seven apparitions from 1910 to 1456 by 93%.
J. L. Brady
semanticscholar +1 more source
Collision probabilities of migrating small bodies and dust particles with planets [PDF]
IAU Symp.263:41-44,2010, 2009 Probabilities of collisions of migrating small bodies and dust particles produced by these bodies with planets were studied. Various Jupiter-family comets, Halley-type comets, long-period comets, trans-Neptunian objects, and asteroids were considered. The total probability of collisions of any considered body or particle with all planets did not exceed
arxiv +1 more source
The end states of long-period comets and the origin of Halley-type comets [PDF]
Monthly Notices of the Royal Astronomical Society, 2016, 2016 We analyze a sample of 73 old long-period comets (LPCs) (orbital periods $200 < P < 1000$ yr) with perihelion distances $q < 2.5$ au, discovered in the period 1850-2014. We cloned the observed comets and also added fictitious LPCs with perihelia in the Jupiter's zone.
arxiv +1 more source
Ion‐Scale Characteristics of the Martian Magnetic Pile‐Up Boundary Layer
Geophysical Research Letters, Volume 52, Issue 3, 16 February 2025.Abstract The Martian magnetic pile‐up boundary (MPB) delineates the interface between the magnetosheath and the induced magnetosphere, but its global ion‐scale characteristics remaining unclear. Utilizing a three‐dimensional Hall magnetohydrodynamic (MHD) model, this study aims to reveal the features of the MPB layer, including magnetic field, current ...
Shibang Li +12 more
wiley +1 more source
Chaotic Dynamics of Comet 1P/Halley; Lyapunov Exponent and Survival Time Expectancy [PDF]
, 2014 The orbital elements of comet Halley are known to a very high precision, suggesting that the calculation of its future dynamical evolution is straightforward. In this paper we seek to characterize the chaotic nature of the present day orbit of comet Halley and to quantify the timescale over which its motion can be predicted confidently. In addition, we
arxiv +1 more source
Journal of Geophysical Research: Atmospheres, Volume 129, Issue 21, 16 November 2024.Abstract Meteoroids of sub‐milligram sizes burn up high in the Earth's atmosphere and cause streaks of plasma trails detectable by meteor radars. The altitude at which these trails, or meteors, form depends on a number of factors including atmospheric density and the astronomical source populations from which these meteoroids originate.
E. C. M. Dawkins +26 more
wiley +1 more source
Waves and Instabilities in Saturn's Magnetosheath: 2. Dispersion Relation Analysis
Journal of Geophysical Research: Space Physics, Volume 129, Issue 10, October 2024.Abstract The WHAMP (Rönnmark, 1982, https://inis.iaea.org/search/search.aspx?orig_q=RN:14744092) and LEOPARD (Astfalk & Jenko, 2017, https://doi.org/10.1002/2016ja023522) dispersion relation solvers were used to evaluate the growth rate and scale size for mirror mode (MM) and ion cyclotron (IC) instabilities under plasma conditions resembling Saturn's ...
I. Cheng +4 more
wiley +1 more source